2015-16 Ligue in 1 -- five burning questions that will shape the season

Ligue 1 returns on Friday, as champions Paris Saint-Germain travel to Lille. The Parisians are again favourites in France, as they take aim at a fourth consecutive league title.

Whether anyone will be able to stop PSG will be Ligue 1's over-arching story, but there are several other key questions that will have serious effects in French football in 2015-16.

1. Will the gambles pay off?

The biggest transfer of the summer in France is without doubt the pending arrival of Angel Di Maria to PSG, but there have been some other very interesting additions to Ligue 1 in this transfer window, and almost all of them can be filed in the "big gamble" category.

Marseille went all-in on Abou Diaby and Lassana Diarra. Neither of the French internationals have played for more than a year, Diaby through injury and Diarra because of a conflict with his former club, Lokomotiv Moscow.

Monaco took lower-stakes risks, but put their money on loan, signing Stephan El-Shaarawy. The 22-year-old Italian international needs to relaunch his career after two disappointing seasons in Milan.

Monaco will be hopeful that Stephan El Shaarawy can rediscover the form that once made him Italy's great attacking hope.

Neighbours Nice placed their chips on Hatem Ben Arfa. The playmaker, still only 28, left Newcastle in January and had to wait six months to join Les Aiglons having already played for two clubs in 2014-15 before signing on the Cote d'Azur. In the meantime, he has only played five-a-side.

Finally, Lyon are hoping to beat the house with the arrival of Rafael from Manchester United and an increasingly likely loan deal for Mathieu Valbuena. The 25-year-old Brazilian played just 11 games last season under new manager Louis van Gaal. Valbuena, on the other hand, spent the last 12 months in the Russian Premier League and might show signs of rust.

Each of these gambles has the potential to pay big dividends. Equally, each could be a complete disaster.

2. Can anyone stop PSG?

Well, everyone can try -- and they will. But after watching PSG during their preseason -- dominating Lyon 2-0 in the Trophee des Champions, easily beating Manchester United 2-0 and impressing in a 1-1 draw with Chelsea -- it looks like the champions mean business already.

Last season, Marseille and Lyon took advantage of Paris' sloppiness in the opening stages of Ligue 1 to take the title race to the wire. Clearly, the Parisians would prefer a stronger start this campaign.

The squad is almost the same -- Yohan Cabaye has departed, Bejamin Stambouli has arrived in his place and Kevin Trapp looks to assume the No. 1 shirt -- but in Di Maria, the Parisians are about to add another world-class player. The good news for the league, though, is that the other contenders (if we can call them that) are stronger than last year, too.

Lyon have recruited well in adding Rafael, Claudio Beauvue, Jeremy Morel and the on-the-way Valbuena. Of more importance, though, the club kept hold of their stars Nabil Fekir, Alexadre Lacazette, Corentin Tolisso and Anthony Lopes.

Monaco completed some very good business in raising €60 million through the sales of Geoffrey Kondogbia and Yannick Ferreira Carrasco. Faithful to their policy, they invested in some very promising young players in Adama Traore, Ivan Cavaleiro, Guido Carrillo, Fares Bahlouli and Mario Pasalic. They also kept hold of 20-year-old Bernardo Silva, one of the revelations of last season, and 19-year-old Anthony Martial.

These teams will inevitably comprise the top four, and while the top spot shouldn't elude PSG, for the other three, it's all to play for.

In his fourth and seemingly final season with Paris Saint-Germain, Zlatan Ibrahimovic will look to top Ligue 1's scoring table once again.

3. Will Ibrahimovic top the scoring charts again?

Zlatan Ibrahimovic lost two scoring titles last season: one to Lacazette for the Ligue 1 scoring crown and to Edinson Cavani for the PSG's top scorer in all competitions. It didn't make the Swede happy at all. For his fourth and seemingly final season in Paris, Ibrahimovic will be desperate to rule the roost once again. He looked very sharp in preseason, even if a knee problem might rule him out of Friday's Ligue 1 opener.

Ibrahimovic is hungry, but he's not the only one. Cavani, who will play in a more central position this season, wants to tip the 30-goal mark. Lacazette, who has been struggling in preseason, will want to confirm his incredible campaign last season. Michy Batshuayi is now the No. 1 striker at Marseille, and had an encouraging season last year serving as Gignac's understudy (nine league goals in 26 appearances but only six starts). And what of Martial, the Monaco prodigy? After playing on a wing for most of last season, he will be the main man up front and could be devastating.

Surely we will be treated to a surprise package at some point. Could it be Beauvue at Lyon, Cheick Diabate or Diego Rolan at Bordeaux, Carrillo at Monaco, Wissam Ben Yedder at Toulouse or Nolan Roux at Saint-Etienne?

4. Same old for Bielsa?

Much of the entertainment in Ligue 1 last season came from Marseille. Not only did the stadium look and sound amazing after the latest stage of refurbishment, but Argentine manager Marcelo Bielsa stole the show as he sat on his cooler and monitored his 3-3-3-1 formation. His team led the table for much of 2014 before crumbling in the second half of the season. Bielsa's philosophy -- the man-marking, the high pressing, the running up and down the pitch -- showed its limits. They missed out on a Champions League qualification place, which was the objective at the start of the season.

But El Loco is back for a new campaign, and with a squad that he has built himself. Gignac, Payet, Imbula, Ayew, Morel and Rod Fanni all left. In exchange, Bielsa got some younger, hungrier and more malleable players. He also signed Milton Casco for a bit more experience at the back and convinced Diaby and Diarra to join his revolution.

Marcelo Bielsa has assembled a Marseille squad in his image and will be expected to guide his side to Champions League qualification.

The summer has been hot and busy in Marseille. Will the season be the same? This time, Bielsa can't fail and has to finish in the top three.

5. Can Lyon do it again?

Achieving one great season is always wonderful, doing it two seasons in a row is even more special. Ligue 1 has had numerous examples in recent years of teams shining one year and disappearing the next, like Montpellier, league winners in 2012 before barely finishing in the top half of the table the following campaign.

Where will Lyon be in 10 months' time? No one expected them to challenge for the title last season. They were in the bottom three after four games and it looked like yet another tough year to come. But they almost beat PSG to win the league for what would have been one of the biggest upsets in its history.

The question is: Can they follow through? Now, everybody will want to beat them. There will be no surprises. Everybody knows how Fekir plays, how Lacazette moves, how Samuel Umtiti defends. And, unlike last season, they will play twice a week with the Champions League now a part of their fixture list. Their recruitment has been promising and the talent is there, but a season is based on much more than that.

For the sake of the club and its fans, let's hope that preseason is not a reflection of their season to come. Humiliated by Arsenal 6-0, beaten 2-0 by Villarreal and dominated by PSG 2-0 in the Trophee des Champions, Lyon have been struggling on the pitch while rumours of unrest in the dressing room are growing. And Lacazette has only converted once so far this summer.

Julien Laurens is a London-based French journalist who writes for ESPN FC and Le Parisien. Follow him on Twitter: @LaurensJulien.